Electric phonograph



Oct. 2, 1934- w. H. GRIMDlTcH 1,975,745

ELECTRIC PHONOGRAPH Filed May 51, 1932 l its ICD Patented @et 2, 1934 riant lPATENT @WCE Application May 31,1932, Serial No. 614,596

1 Claim.

This invention relates to improvements in electric phonographs and particularly to devices which combine such a phonograph with a radio receiver in a single cabinet, the phonograph pickup in such case being connected to the sound reproducer through one or more of the audio frequency amplifying tubes of the radio receiver as is well known.

An object of the invention is to provide an electric phonograph which will not be susceptible to mechanical vibrations particularly cabinet vibrations generated by the speaker which heretofore have been a source of annoyance, since they cause Y Vibration of the electrical pick-up Which translates the vibrations into electrical impulses that are translated into sound by the reproducer. This action is very pronounced in modern devices utilizing sensitive ampliiiers and sound reproducers which respond readily to the low frequency impulses and greatly amplify the same.

Another object oi the invention is to provide a device of the nature above specied in which vibration of the electrical pick-up relative to the sound record is substantially prevented, these elements, together with the driving motor for the record-supporting member, being resiliently mounted as a unit. ln addition to preventing extraneous vibrations from affecting the pick-up, the resilient mounting reduces oscillation of the system and sustained regeneration of the sound being reproduced from the record and translated into electrical impulses.

Reference may be had to the following description ier a complete understanding of the invention which is illustrated in a preferred form on the accompanying drawing, the single iigure of which is an elevational view of a combination electrical phonograph and radio-receiving device, certain parts being shown in section for clarity of illustration.

Referring to the single view of the drawing. there is disclosed at 1 a cabinet having a hinged top 2 permitting access to the electrical phonograph designated generally by reference character 3. The cabinet also houses a radio receiver 4', the elements of which, in the present instance, are mounted upon a support 5 extending transversely of the cabinet walls and supported thereby. A sound reproducer 6 is mounted on the front panel of the cabinet adjacent opening 7 as is customary. The phonograph, the radio receiver, and the sound reproducer may be of any conventional type, those illustrated being merely for the purpose of this disclosure.

The phonograph comprises the usual elements of such device. In the present instance, a common supporting member 8 is provided for the various phonograph elements. The driving motor 9, which, of course, preferably takes the form of an electric moto-r supplied from the same source as supplies the radio receiver, is suspended from the lower surface of support 8 by means of resilient springs 10. The reccrd--supporting member ll, which, in the present instance, is in the form of a turn-table, is rotatably mounted and driven by motor 9 through shaft l2, which is suitably connected to the rotating armature shaft of the motor through reduction gearing 13. The tone arm i4 is pivotally mounted at one side of support 8 and carries at its free end the usual electrical pick-up which is adapted to cooperate with records placed upon turn-table 1l, all of which is well known. The pick-up is electrically connected to the reproducer through a part of the radio receiver ampliiier in the conventional manner above mentioned.

In accordance with the present invention, the various phonograph elements are floatingly mounted as a unit Within cabinet l by resiliently supporting the common support 3 within the cabinet. To this end, the transversely-extending supporting structure i6 is carried by the walls of the cabinet and formed to pro-vide a seating ledge 17 upon which one or more resilient supporting members 18 yare disposed. The supporting member or members 18 may take the form of a single ring-like element or may comprise a plurality of spaced blocks. Preferably, the supporting element or elements are formed of rubber but springs or any other material having the desired resiliency may be used. The function of the resilient supporting means, whatever its iorm, is to resiliently support the common supporting member 8 so as to resiliently mount the phonograph elements as a unit with respect to the cabinet.

It will be apparent from the present disclosure, that the contemplated mounting of the phonograph substantially prevents cabinet vibrations from affecting the electrical pick-up and causing it to generate corresponding electrical impulses. In other Words, the resilient supporting means acoustically insulates the phonograph from the cabinet. It will also be noted that by virtue of the unitary floating mounting of the phonograph elements, vibration of the pick-up relative to the record is substantially prevented.

Inasmuch as vibration of the pick-up relative to the record is substantially prevented by virtue of the present invention, resonance and sustained regeneration of sounds being reproduced from the record is substantially reduced and singing on low reproduced notes is like- Wise substantially reduced.

While the invention relates generally to electric phonographs, it is particularly useful in devices of the type disclosed herein or any similar device Where the electrical impulses generated by the pick-up are greatly amplied. As previously stated, the highly sensitive amplifiers and reproducers used in modern devices respond more readily to objectionable impulses and reproduce the extraneous and objectionable noises in a very pronounced manner. This invention, by preventing the objectionable impulses from being generated and passed to the amplifiers and reproducer, eliminates the objectionable reproduction of the noises.

Although a single preferred embodiment of the invention is disclosed herein, it Will be understood that various modications or changes may be made Without departing from the spirit and scope of the invention.

I claim:

In a device of the class described, a record supporting member, means for driving said member, an electrical pick-up adapted to cooperate with a record carried by said member, a common support for the aforesaid elements, a cabinet, means for resiliently mounting said common support in said cabinet, whereby the elements carried by said common support are resiliently mounted as a unit, a radio receiver and a sound reproducer therefor mounted in said cabinet, and means for electrically connecting said pick-up to said sound reproducer through one or more of the audio frequency amplifiers of said radio receiver.

WILLIAM H. GRIMDITCI-I. 

